// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef BASE_VLOG_H_
#define BASE_VLOG_H_

#include <string>
#include <vector>

#include "base/base_export.h"
#include "base/macros.h"
#include "base/strings/string_piece.h"

namespace logging {

// A helper class containing all the settings for vlogging.
class BASE_EXPORT VlogInfo {
public:
    static const int kDefaultVlogLevel;

    // |v_switch| gives the default maximal active V-logging level; 0 is
    // the default.  Normally positive values are used for V-logging
    // levels.
    //
    // |vmodule_switch| gives the per-module maximal V-logging levels to
    // override the value given by |v_switch|.
    // E.g. "my_module=2,foo*=3" would change the logging level for all
    // code in source files "my_module.*" and "foo*.*" ("-inl" suffixes
    // are also disregarded for this matching).
    //
    // |log_severity| points to an int that stores the log level. If a valid
    // |v_switch| is provided, it will set the log level, and the default
    // vlog severity will be read from there..
    //
    // Any pattern containing a forward or backward slash will be tested
    // against the whole pathname and not just the module.  E.g.,
    // "*/foo/bar/*=2" would change the logging level for all code in
    // source files under a "foo/bar" directory.
    VlogInfo(const std::string& v_switch,
        const std::string& vmodule_switch,
        int* min_log_level);
    ~VlogInfo();

    // Returns the vlog level for a given file (usually taken from
    // __FILE__).
    int GetVlogLevel(const base::StringPiece& file) const;

private:
    void SetMaxVlogLevel(int level);
    int GetMaxVlogLevel() const;

    // VmodulePattern holds all the information for each pattern parsed
    // from |vmodule_switch|.
    struct VmodulePattern;
    std::vector<VmodulePattern> vmodule_levels_;
    int* min_log_level_;

    DISALLOW_COPY_AND_ASSIGN(VlogInfo);
};

// Returns true if the string passed in matches the vlog pattern.  The
// vlog pattern string can contain wildcards like * and ?.  ? matches
// exactly one character while * matches 0 or more characters.  Also,
// as a special case, a / or \ character matches either / or \.
//
// Examples:
//   "kh?n" matches "khan" but not "khn" or "khaan"
//   "kh*n" matches "khn", "khan", or even "khaaaaan"
//   "/foo\bar" matches "/foo/bar", "\foo\bar", or "/foo\bar"
//     (disregarding C escaping rules)
BASE_EXPORT bool MatchVlogPattern(const base::StringPiece& string,
    const base::StringPiece& vlog_pattern);

} // namespace logging

#endif // BASE_VLOG_H_
